A co-worker sent this to me today. I haven't researched it. I did a forum search for Mabru but nothing came up.
The price is expensive.
https://mabrustore.com/12v-dc-mabru-mar ... nditioner/
I did find a youtube video for their Mabru Power Systems 4,200BTU Marine Self Contained unit w/ Reverse-Cycle Heat and Digital Control
https://www.youtube.com/watch?v=eSk5mPDjXyE&t=190s
Here are some of the other options
https://mabrustore.com/marine-air-conditioning/
I'm just throwing this out there for discussion purposes. If a 12v A/C unit was a reasonable price is it feasible for off grid option?